Triangular Nickel Complexes Derived from 2-Pyridylcyanoxime: An Approach to the Magnetic Properties of the [Ni3(μ3-OH){pyC(R)NO}3]2+Core

A series of nickel complexes with nuclearity ranging from Ni3 to Ni6 have been obtained by treatment of a variety of nickel salts with the 2-pyridylcyanoxime ligand. The reported compounds have as a common structural feature the triangular arrangement of nickel cations bridged by a central mu 3-oxo/alkoxo ligand. These compounds are simultaneously the first nickel derivatives of the 2-pyridylcyanoxime ligand and the first examples of isolated, mu 3-O triangular pyridyloximate nickel complexes. Magnetic measurements reveal antiferromagnetic interactions promoted by the mu 3-O and oximato superexchange pathways and comparison of the experimental structural and magnetic data with DFT calculations give an in-depth explanation of the factors that determine the magnetic interaction in this kind of system.